Work-feed fixture for grinding machines



Feb. 7, 192 8.

J. MILLER, JR

WORK FEED FIXTURE FOR GRINDING MACHINES Filed Jan. 29. 1927 2 Sheets-Sheet 1 l izio'enzap Feb. 7,1928.

J. MILLER, JR

WORK FEED FIXTURE FOR GRINDING MACHINES Filed Jan. 29, 1927 2 Sheets-Sheet 2 Jam #1171?!) M I MW %6l Patented 7, 1925.

sense ra'rsNr QFFICE.

Joint M LLER, JR, OF B iLoIT, Wisconsin, 'As'sionon To CHARLES H. BESLY ND COMPANY, on oH cAdo, ILLINOI n QORPORATION or ILLINOIS.

WORK-FEED m xirun'n F03 c'mniame MACHINES,

App i ion flee Je n r! 9, .9. 1 s ria o- ,3

This invention relates to improvements in work feed fixtures for grinding Inaehine$ and more particularly to inaehines fo Operating en elat elysmel cir lar pieces of work, such as piston rings, Whieh are continuously fed between the grinding discs of the machine.

A machine for a similar purpose is closed in lily copending. application, Serial No. 164,388, filed January 29, 192 7, whet the work was fed automatically iron; a magazine, thence along a track passing between iced rolls and "positively he y e W- e he gr n ns es:

The grinding machine herein to be described operates in substantially the sa nt; manner as above set forth but structurally in the feed nechanis n intermediate the work magazine and the feed rolls, which in this instance consists of an oscillating plate. r

Since the, two machines are. otherwise sirn; ilar in purpose and operation, the present disclosure will be confined to the feed mechanisin and associated parts, reference being made to the machine as a whole only where such is necessary to a full u nclerstanding of its operation. i

In the accompanying drawings,

Figure 1 is a general view in side elevation of the'feeding mechanism with parts broken away and shown in section; and

Figure 1. is a View in vertical section taken on line 1 1 of Figure 1. v

Figure 2 is an enlarged detail View in vertical section through the work; feeding mechanism as taken on line 2-2 of, Figure 1.

Referring in general to the machine embodying the invention, the same comprises a frame 1. supporting two sliding carriages 2 on which are journallcd horizontal spindles having grinding discs 3 mounted at their inner ends and located centrally ot the machine. Figure 1 shows only one of the grinding discs, its associated disc being oppositely disposed with a] relatively narrow space between. the work being advanced edgewise between the two, grinding faces. For guiding the workbetween the discs there are two horizontal parallel guide bars 4, 44 supported at each end bysuitable brackets attached to the machine train e and connected together on either side of the grinding discs by transverse guide plates 5, 5 between which the upper bar 4 is free to move, the latter be ngsnspended from brackets 6, 6 With springs 'Z, 7 acting downwardly on the bar. A semi-lee eser t n of e Wo kg d means'is not essential to the understanding c the haters mb y g he p n lQSur-e, since is read ly apparent that any .J le emai fo id ng h Work through the gp' nding zone will serve the purpose.

1mm diately forward ofthe grinding discs s the Week-feed n mech s which y rega ded. eith r a n tach t h srie is ma ine r ps: er a n integral gar a as e teine e f e g d n chi e- ;he seneg er th f ed n mechanism is a or ed casting 8 fixed to the front of the machine frame 1 and adjustable for both vertical and horizontal movement, an elevating screw 9, serving both as a floor support and means for elevating the bed cast ing. the center of the bed casting 8 is a pair of vertical feed rolls 10, 10 of a re- Inaterial, such as rubber, these rolls bein mounted on spindles journ alled at top andgottoin in bearings 11 and 12and driven tr mtheir lower ends by gearing hereinafter to described. The feed rolls are spaced relatively close together, the distance being approxim tely the thickness of the work to be ground. s a Extending between the feed rolls and at right angles to the axis of the grinding discs, c

i518 track l3 consisting of a plate supported on edge with its upper edge forming the track surface, extending horizontally in line with the bottom edges of the feed rolls. This track plate 13 is fixed and extends in both directions from the feed rolls, joining the'guide bar 4 at its rear end and extending almost to the front edge of the bed whererit is bolted to a supporting bra ket 14-.

Immediately to the left (Figure 2) of the track plate-.13 near its forward end is a. work n agazine 15, consisting of a V-shaped trough in which the work A is stacked on edge, which in the drawings isillustrated as piston rings a. The discharge end of the trough terniinetesjust above and in the V61- tica]. plane of;- theleft-hand face Qfthe track plate 13. In the trough is a pusher block 16 mounted at the forward end of a sliding rod 17 which is actuated by a Weight and cable (not shown) whereby the pusher block presses against the work and forces the rings successively from the magazine onto the track. I

Just opposite the discharge end of the magazine and above the track plate 13, is an oscillating pusher plate 18 moving toward and from the feed rolls, that is to say,-

during one stroke the pusher plate isearried forwardly beyond theend of the magazine permitting a ring to be discharged onto the track and in frontof the edge of the pusherplate, and on the next stroke, the ring is carried toward the feedrolls, each ring so advanced pushing the rings ahead of it along the track.

With this general explanation of the feeding action, the push plate and its actuating mechanism as well as that of the feed rolls, will now be described more in detail.

Mounted on the bed casting 8 and extending beneath the feed rolls and pusher plate, is a casing 19 in whicli the driving mechanism is located, said casing being adapted to be partially filled with oil for lubricating themoving parts. Extending transversely hearings on opposite sides thereof, is a shaft 20. This shaft is driven by a motor 21 mounted at the right side of the'b'ed casting through the following intermediate parts: The motor drives directly to a shaft 22 extending transversely of the shaft 20 above its right end, through a belt 23 and pulleys 24 and 25 mounted on the armature shaft of the motorand the end of the shaft 22 respectively, the portion thereof carrying the pulley 25 being exterior ofthe casing 19. The shaft 22 drives the shaft 20 through a worm 22 and worm wheel 2O mounted on the shafts 22 and 20, respectively. 1

Theopposite or left end of the shaft 20 extends through the adjacent side wall of the casing 19 intoa ehange gear box 24. Extending immediately behind it, is a countersha-ft 26 likewise iournalled in. the side walls of the casing and having its left end extending into the gear box 24;. The shaft 20 carries a pinion27 meshing with a gear wheel 28 onthe countershaft 26, these gear members beinginterchaiureable with other sets of gear members of different Q6211 ratio for the purpose of decreasing or increasing the speed of the countershaft 26 relative to the shaft 20, whichmay be regarded as the primary drive shaft and driven at a constant speed. Mounted on the countershaft 26 (Figure 1) are spiral pinions 29 which mesh with com plementary pinions 30 mounted, at the lower ends of the feed roll spindles 31 which extend beyond their lower bearings 12 into The rock shaft extends the casing of the casing and journalled in parallel with the shaft 20 and the casing; 19. The pairs of food roll drive the rings toward the grinding discs as they ed between them.

Going back to the primary drive shaft 20, the drive from this shaft to the pusher plate will now be described: 7

immediately above the shaft 20 and parallel therewith is a rock sha 't 32 journalled in'bearingjs at opposite sides of a vertical extension 33 of the casing 19 at its left. side. from the inner side ofthe casing extension below the track plate and on this end of the shaft and exterior of is mounted the pusher. plate are 'l:

assembly.

The drive from the shaft 20 to the rock shaft32 is through a combined. eccentric and friction clutch mechanism. Keyed'to the shaft 20 is an eccentric sheave 34 carry-. v ingran eccentric strap 35 having an arm 35* ending," vertically and pivotally connected ivith the end of a rocker arm 36 fixed tothe rock shaft '32. On either side of the eccentrie sheave o-L are friction discs 37 and 38, V 1

the disc 87 on the left being 'fixed'to shaft 20, whereas the disc 38011 the right turns withjth-e shaft but is capable of a limited moven ient along the shaft, this being accom i ied by a piu'38 engaging a slot or key- 39 in the shaft.- Beyond the shiftable on disc is a spring 40 surrounding the i 20 andbearing at itsouter end against an adjustablecollar 4-.1 having screw threaded engagement with the shaft. Thus by turning the collar in either direction, the tension of the springis correspondingly increased or decreased and the pressure exert ed by the spring on the shiftable disc is ch any d in like degree to increase or decrease the friction betweenthe discs 37 ant 38 on the eccentric sheave A set sc'rew ll in the collar serves to normally lock the collar on the shaft, this set screw being accessible through an opening in the casing wall above, which is closed by a screw ,pl up; 4E2.

Thus it will be seen that the power is de livered'from the shaft 20 to the eccentric strap and arm through the friction discs 87 and 38 and the eccentric sheave 34-, and'as a result any resistance met by the pusher plate in its movenient is compensated for by the slippage between the friction surfaces. if Forthe purpose of lubricating the rocker shaft lgiearings, an oiler chain driven by a"sprocltet wheel 44 on the shaftf20 and pas-:singaround a grooved, collar 4:5 on the rocker shaft, is provided.

RQfQYIlHQJlOM to the details of the pusher plate l8,' the same is a metalplate of substantially the same thickness as the track plate 13 and soniewha't irregula in shape, but q enerallyrectangular and elongated in a longitudinal direction; At its forward edge it has a rounded lip 18 to better engage the work and carry it forward during the feeding stroke. Cooperating with the pusher plate is a fixed'guide plate 46 secured to the track. plate 13 on the opposite side from the discharge end of the magazine, and extends lengthwise throughout the path of the pusher plate, which it will be noted from Figure 1, is from a point forwardly of the magazine to the entrance between the feed rolls 10, 10.

The pusher plate moves in a vertical plane immediately above the track 13 and is carried at the upper end of a rocker arm 47 offset therefrom on the opposite or right side of the guide plate 46. The rocker arm assembly consists of several parts as follows: Keyed to the rock shaft 32 is a collar 48 having radial arm 48* extending upwardly. At the extreme end of the rock shaft is a lever arm e9 loosely journalled on the shaft and extending upwardly beyond the arm 48* to the top edge of the guide plate e6. Intermediate the ends of the lever arm 4-9 is a slotted sector 49 through which passes an adjusting screw 50, anchored in the end of the radial arm 48* of the fixed member 48 on the rock shaft. The lever arm 49 carries an endwise adjustable arm 51 bearing against the upper portion of the lever arm 49 and slotted lengthwise to take an adjusting screw 51. The upper end of the arm 51 is bent at right angles toward the pusher plate and clearing the top edge of the guide plate 46, is fixed to the pusher plate at its upper edge and between its ends.

By the foregoing arrangement, the length of the rocker arm can be adjustedto raise or lower the pusher plate. Similarly, the rocker arm 47 can be shifted relative to the axis of the rock shaft 32, so as to vary the stroke. these two adjustments making it possible not only for different sizes of work to be handled in the machine but the rate of feed to be regulated so that the work will be advanced to the feed rolls at the proper intervals. 7

The operation of the feeding device will be readily understood from the following: As the pusher plate is moving forwardly and clears the end of the magazine, a ring a is forced into its path against the guide plate as and rests on the track plate 13, and on the succeeding feeding stroke oelivers the ring to the feed rolls where it is immediately picked up and carried onward at the peripheral speed of the rolls forcing or pushing the preceding rings ahead of it into and through the grinding zone.

In feeding the work to the feed rolls, it is desirable that the rings shall move for ward in contact with each other, and hence the purpose of the several adjustments as delivered to the feed rolls, is held momen- 'ta ri'ly. in retarded'position against the preceding ring and thusfollows it throughthe feed rolls in close contact. Thus the cntire feeding operation is made automatic and continuous without breaks or interruptions from one end of the grinding operation to the other.

Having set forth the novel features of the n'iechanism embodying my invention, I claim:

1. In a work feeding device for grinding machines, the combination of a pair of grinding discs,'means for advancing the work to be ground between said discs including an oscillating feed plate moving toward and from said grinding discs, a rock shaft supporting said feed plate and provided with a rocker arm, a drive shaft extending parallel with said rock shaft, an eccentric sheave turning loosely in said drive shaft, an eccentric strap and rod connecting said sheave with said rocker arm, and friction clutch members mounted on said drive shaftand engaging said eccentric sheave.

2. In a work feeding device for grinding machines, the combination of a pair of grinding discs, means for feeding successive pieces of work between said discs including an oscillating feed plate, a rock shaft supporting said feed plate and provided with a rocker arm, a drive shaft extending parallel with said rock shaft, an eccentric sheave turing loosely in said drive. shaft, an eccentric strap operatively connected with said rocker arm, friction discs mounted on said drive shaft and embracing said eccentric sheave and tension means actingo-n said discs.

3. In a work feeding device for grinding machines, the combination of a pair of grinding discs, means for advancing the work to be ground between said discs including an oscillating feed plate moving toward and from saic grinding discs, a rock shaft supporting said feed plate and provided with a rocker arm, a drive shaft extending parallel with said rock shaft, an ec centric sheave turning loosely in said drive shaft, an accentric strap and rod connecting said sheave with said rocker arm, friction iscs mounted on said drive shaft oneither side of said sheave, a spring acting on one of said discs to press the same together to frictionally engage said sheave, and means for adjusting the tension of said spring.

4. In a work feeding device for grinding machines, the combination of a pair of grinding discs, means for advancing the work to be ground between said discs including an oscillating feed plate moving toward and from said grinding discs, a rock shaft, an endwise adjustable lever arm mounted on said rock shaft and carrying said feed plate, a drive shaft extending parallel with said rock shaft, an eccentric sheave turning loosely in said drive shaft,

an eccentric strap operatively connected with said rock shaft, friction CllSCS mounted Lesspes January, 1927.

- JOHN MILLER, J R. 

